8.4 - Similarity Theorems...8.4 Similarity Theorems Mental Floss: Fri, Feb 16th In the diagram below, . Find the following: a.) b.) c.) Perimeter of d.) Ratio of the area of e.) Scale

8.4 ­ Similarity Theorems

Mental Floss:  Thurs, Feb 15th

Example #2 Example #3

8.4 ­ Similarity Theorems

Mental Floss:  Fri, Feb 16thIn the diagram below,                          .  Find the following:

a.)

b.)

c.)  Perimeter of

d.)  Ratio of the area of

e.)  Scale factor from         

10 15

20

6

A B

C

DE

Theorem:  Three Parallel Lines Theorem

If three or more parallel lines intersect two transversals, then they divide the transversals proportionally.

a b

c d

l m p

s

t

Example #4 Theorem:  Triangle Angle Bisector Theorem

If a ray bisects an angle of a triangle, then it divides the opposite side into segments whose lengths are proportional to the lengths of the other two sides.

a

b

c

d

Example #5 Homework6.4 p.333#11­16,21

8.4 p.450#4,7,8,13­16,18,21­26,29,30,34,43­45